Neuropathology Flashcards
What are the 3 layers of mater called?
Dura mater
Arachnoid mater
Pia mater
What is a red neuron?
A pathological hallmark of lethal injury to a neuron brought about by hypoxia or ischaemia.
Results in cell death.
What neuronal change occurs in response to chronic degenerative disease?
Simple neuronal atrophy
What are sub-cellular alterations of neurons also known as?
Inclusions
Common in AD.
What cells are affected in demyelinating disorders?
Oligodendrocytes
What is the role of astrocytes?
Maintenance of the blood brain barrier.
What is the process by which astrocytes produce scar tissue?
Gliosis
This is the most important indicator of CNS injury.
How do microglia respond to injury in the brain tissue?
Through proliferation and aggregation.
What are microglia?
The macrophages of the CNS.
What artery is most commonly affected by a thrombus to the Circle of Willis?
Middle cerebral artery
What % of the cardiac output goes to the brain?
Around 15%.
What is a common precipitating factor in infarct and haemorrhagic strokes?
Hypertension
What causes global ischaemic damage?
Systemic compromise which is not compensatable.
What causes focal ischaemic damage?
The restriction of blood flow to a particular area of the brain.
Are glial cells more susceptible to hypoxic injury than neurons?
No, neurons are.
These will be injured first.
How long does a TIA last?
Less than 24 hours.
How long does a stroke last?
Over 24 hours.
How long does it take for liquefactive necrosis to develop?
Months
What is reactive gliosis?
The process by which astrocytes increase in both number and size.
What can severe hypertension precipitate in the brain?
Hypertensive encephalopathy
What is amyloid angiopathy?
When abnormal protein sheets are deposited in the cerebral and meningeal vessels.
Makes them less likely to cope with increased pressure.
What are the most common congenital vascular abnormalities?
Arteriovenous malformations
Where is the most common site of an arteriovenous malformation?
Middle cerebral artery
What is the most common cause of spontaneous subarachnoid haemorrhage?
Saccular/Berry aneurysm
Is subarachnoid haemorrhage more common in women or men?
Women
What are symptoms of a subarachnoid haemorrhage?
Abrupt onset headache
Vomiting
LOC
What is the role of the falx cerebri?
To separate the cerebral hemispheres.
Where is CSF produced?
Lateral ventricles
What is the role of the CSF?
Prevent injury to the brain
Clear waste
Are any cells present in a normal CSF sample?
No
If lymphocytes are seen in CSF, what does this indicate?
Viral infection
Fungal infection
Autoimmune disease
Raised neutrophil levels in the CSF are seen in what?
Bacterial infection
Low glucose in the CSF indicates what?
Bacterial infection (TB most commonly seen with this) Fungal infection
What is a hydrocephalus?
An accumulation of excessive CSF within the ventricular system.
What can cause hydrocephalus?
Obstruction to CSF flow
Decreased resorption
Overproduction of CSF
What is hydrocephalus ex vacuo?
The dilatation of the ventricles due to loss of brain parenchyma.
There is no raised ICP.
Where is brain metastasis commonly found?
The boundary between the grey and white matter.
What is a grade IV astrocytoma called?
Glioblastoma
What is the most common tumour in kids?
Medulloblastoma
These occur at the midline, can cause hydrocephalus (if the flow of CSF is disrupted).
What do multiple abscesses indicate?
Haematogenous spread
How is a cerebral abscess diagnosed?
CT or MRI.
There will also be signs of infection and a raised ICP.
What is bacterial meningitis?
Inflammation of the meninges due to bacteria.
A medical emergency.
What are the two categories of head injury?
Penetrating
Blunt
What is a key determinant in head injury severity?
Velocity
Is primary brain injury reversible?
No, it is irreversible.
What is a clinical hallmark of a primary brain injury?
Immediate cessation of consciousness level.
What is a coup injury?
Injury at the side of the impact.
What is a contracoup injury?
Injury diametrically opposite the point of impact.
Is contracoup or coup injury worse?
Contracoup injury is worse.
Disruption of what structures lead to the development of a subdural haematoma?
Bridging veins.
Where do subdural haematomas occur?
Between the dura mater and arachnoid mater.
Which patients usually present with a subdural haematoma?
Elderly patients with a clear history of trauma.
In MS. what is commonly seen in the CSF?
Oligoclonal bands
How does demyelination appear on a T2 weighted MRI scan?
Hyperintense regions
What is the most common pattern of MS
Relapsing/Remitting
Are MS plaques distributed symmetrically?
No
What follows neuronal atrophy in degenerative disease?
Gliosis
Is dementia a disease of symmetrical neuronal involvement?
Yes
What is the most common form of dementia?
Alzheimer’s disease
What are neurofibrillary tangles?
Bundles of insoluble microtubules within the cytoplasm of neurons.
Presence associated with AD.
What mode of inheritance is seen in HD?
Autosomal dominant
It is a trinucleotide repeat disorder.
